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Appendix VI.

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three stresses j^/s and/b have the relative values of i, f,  and 2.
Bearing stress is to be taken into account.

The rivet shear, the plate tension, and the rivet bearing will have
the respective strengths

(i)                    to                   (3)

Combining (i) and (3) we have

y*-*   ,./.

And by (2) and (3), substituting for d,

For %' plates the values will be

2x4

3    =12

2X4

-<M         3     X3-£i

This problem is interesting from a theoretical standpoint, but the
proportions could not be adopted, for practical reasons of manufacture,
such as the difficulty of riveting and of procuring staunchness.

The following investigation is due to Prof. Pullen :

Let d-= 1-3 Jf (as on p. 407), and let the ratio of/b to/s = 2.

Comparing the strength of the rivet for shearing and bearing we

have, in Single Shear,

1*02

.'. When

,

and 7- =

t  =    -2        •        =    2-28

/s

t - -3.

t - '4

-     = r86

~} = 1-62

/s

shewing that bearing surface is- ample when / is ^ in. and over.```